1. Field of the Invention
The present invention is in the field of pressure injectors, relating particularly to a mechanism for introducing effective dosages of liquid medicament into the skin of a human or an animal or the stalk or other surface of a plant and so forth without the use of hypodermic needles.
2. The Prior Art
It is known, in lieu of hypodermic needles, to administer dosages by directing a stream of medicament, for example, under high pressure against the skin of the subject.
As pointed out in co-pending application Ser. No. 380,357, now U.S. Pat. No. 3,859,996, the total amount of fluid expelled from the dosage orifice may not be effectively introduced into the body of the subject. Additionally, the depth of penetration and the direction of penetration of a dosage into a subject varies the physiological effect of the medication on the subject. As further noted in the above mentioned application, the effective dose administered may depend on the angle of the orifice with respect to the subject at the instant of transfer, as well as the pressure with which the orifice contacts the subject.
In the aforementioned application there is disclosed a novel triggering mechanism for a pressure inoculator which prevents discharge of the apparatus unless portions of the apparatus are positioned against the skin surface of the subject. The device, to a degree, tends to aid in the orientation of the orifice relative to the surface of the subject.